1. Field of the Invention
The present invention relates to a scanning endoscope that photographs and/or films an optical image of a subject that is around an insertion tube of the scanning endoscope.
2. Description of the Related Art
Japanese Patent No. 3943927 discloses a scanning endoscope which photographs and/or films an optical image of an observation area by scanning the observation area with light shined on a minute point in the area and successively capturing reflected light at the illuminated points. In a general scanning endoscope, light for illumination is transmitted through an optical fiber from a stationary incident end to a movable emission end and a scanning operation is carried out by successively moving the emission end of the optical fiber.
A general scanning endoscope is designed so that a field of vision of the scanning endoscope is in front of a distal end of an insertion tube of the scanning endoscope. However, it is difficult to observe certain types of subjects using such a scanning endoscope. This is because it is difficult to adjust the position of the insertion tube in a thin lumen, such as a bronchial periphery, so that the distal end of the insertion tube faces the inner surface of the thin lumen. Accordingly, the inner surface of a thin lumen is photographed and/or filmed at a large angle of incidence with respect to the inner surface to be photographed and/or filmed. However, it is difficult to recognize the status of the inner surface by the image of the inner surface photographed and/or filmed from such a large angle of incidence.